Feed a sourdough starter 4-12 hours before starting the bread, ensuring it is active and bubbly.
In a large mixing bowl, combine warm water, flour, sourdough starter, and salt with your hands, a wooden spoon, or dough whisk.
Cover with plastic wrap or damp towel and let the dough rest for 30 minutes.
Add chopped rosemary before performing the stretch and fold technique.
Stretch And Folds
Stretch and folds are accomplished by grabbing the edge of the dough and pulling it up, gently shaking it as it stretches upwards. Next, push the stretched dough back into the center. Turn the bowl about a quarter turn and do this process again, turn the bowl and repeat. Complete the stretch and fold a total of 3-4 times. This is considered one round, repeat for a total of 6 rounds.
First 3 stretch and folds – every 15 minutes.
Last 3 stretch and folds – every 30 minutes.
Cover with a lid or plastic wrap and allow the dough to rise until doubled in a warm place.
Place dough on a clean work surface.
Split the dough in half down the middle with a bench scraper. Try to be careful not to break any of the bubbles.
Shape into a ball by gently spinning it toward you in a circular motion.
Set out 15-20 minutes uncovered. This allows a skin to develop.
Turn over and shape.
Transfer to floured banneton or a bowl lined with a tea towel (I like to use rice flour). Another option is an oiled bowl. Cover with plastic and proof for 12-15 hours in the refrigerator.
The next morning, preheat the dutch oven on 500 for 1 hour.
Remove dough from the fridge immediately before scoring and baking.
Dust with flour on top to make the scoring pattern stand out more.
Score the top of the dough with a razor or lame. Place the dough on a piece of parchment paper for best results and transfer to the dutch oven. Careful it is hot.
Bake for 20 minutes at 500 with the lid on.
Turn the oven temperature down to 475, remove the lid, and bake an additional 25 minutes or until browned.